In semiconductor devices with a multilayer structure obtained by layering a plurality of semiconductor chips, the semiconductor chips are usually bonded together using a die bonding adhesive. It is desired that the adhesive has a combination of properties including a low-stress property, low temperature attachability, moisture-proof reliability and solder reflow resistance.
In production of a semiconductor device with a multilayer structure, it is common to bond semiconductor chips together by situating a die bonding adhesive between a buffer coat film formed on a circuit surface of a semiconductor chip as a lower layer, and a semiconductor chip positioned on that upper layer. The buffer coat film of the semiconductor chip is patterned using a photosensitive resin, so that openings are formed where the bonding pads are exposed.
Also, several photosensitive adhesives having both photosensitivity and adhesion property have been proposed (see Patent documents 1-3).
[Patent document 1] Japanese Unexamined Patent Publication No. 2000-290501
[Patent document 2] Japanese Unexamined Patent Publication No. 2001-329233
[Patent document 3] Japanese Unexamined Patent Publication HEI No. 11-24257